ERCOT expects to have sufficient resources this fall and winter: reports

Houston — The Electric Reliability Council of Texas' latest resource adequacy assements for fall and winter show growing excesses of resources over peakloads under various scenarios, but natural gas prices may be a bigger factor in power prices during those period, an analyst said Sept. 3.

ERCOT on Sept. 3 released its final Fall 2020 Seasonal Assessment of Resource Adequacy and its preliminary Winter 2020-21 SARA and declared that the grid operator expected to have "sufficient generation" for both seasons.

ERCOT's final fall peak power demand forecast, at 60,966 MW, is unchanged from its preliminary forecast issued in May.

"ERCOT anticipates there will be more than 86,000 MW of resource capacity available at the start of the fall season, including 1,475 MW of planned wind and solar capacity that is expected to be available during fall peak demand periods," ERCOT said in a news release. "This fall SARA includes a unit outage forecast of 14,267 MW, which is based on the historical average of outages for weekday peak hours for each of the last three fall seasons."

Growing surpluses

With the forecast peakload and typical generation outages, the final fall 2020 SARA, which just covers the months of October and November, indicates that resources should exceed demand by 10.8 GW, compared with the final fall 2019 SARA's difference of 9.1 GW.

Asked whether the increased supply might translate into lower power prices, Joshua Rhodes, a research associate at the University of Texas Energy Institute's Webber Energy Group said that, other things being equal, "more renewables should still be reducing overall system costs, but natural gas is still the driver for prices most of the time, so it will depend on how those prices compare."

In the same scenario for the winter of 2020-21, December through February, the preliminary SARA indicates that resources should exceed demand by 16.6 GW, up from less than 13 GW in the final SARA for the winter of 2019-20.

ERCOT noted in its news release that it expects to have 1,359 MW of planned generation capacity to be available before the Dec. 1 start of ERCOT's official winter season.

Low wind scenario

"Due to the increased amount of renewables on the ERCOT system, the grid operator has also included a low wind output scenario in the preliminary winter SARA," ERCOT said. "Moving forward, ERCOT will begin including a low wind output scenario in all of its seasonal assessments."

With forecast peakload and extremely low wind output, ERCOT's resources would still exceed peakload by 1,871 MW this fall and by 11.2 GW this winter, the SARAs show.

ERCOT plans to release the final winter SARA for 2020-21 in early November.